This application is based on and claims priority under 35 U.S.C. xc2xa7 119 with respect to Japanese Application No. 2000-049437 filed on Feb. 25, 2000, the entire content of which is incorporated herein by reference.
The present invention generally relates to a convertible top of a vehicle. More particularly, the present invention pertains to a control apparatus for opening and closing a vehicle convertible top having a locking mechanism which is arranged between a movable roof and a vehicle body as well as a driving mechanism which is coupled to the locking mechanism to drive the locking mechanism in a locked condition and an unlocked condition.
An example of a known control apparatus for opening and closing a convertible top of a vehicle is disclosed in U.S. Pat. No. 4,749,193. The convertible top includes a locking mechanism and a driving mechanism. The locking mechanism is arranged between a movable roof and a vehicle body to hold the movable roof of the vehicle body in a fully closed position. The driving mechanism is coupled to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition. The control apparatus also includes a limit switch, a position sensor and a control unit. The limit switch outputs a first signal indicating that the movable roof is closed. The position sensor outputs a second signal indicating that the locking mechanism is in the locked condition. The control unit controls the driving mechanism according to the first signal and the second signal. The control unit effects the driving operation of the driving mechanism when the first signal is inputted to the control unit from the limit switch. Further, the control unit stops the operation of the driving mechanism when the second signal is inputted to the control unit from the position sensor. Therefore, the locking mechanism is turned to the locked condition from the unlocked condition when a signal inputted to the control unit is switched from the first signal to the second signal.
In the above mentioned known control apparatus, while the limit switch outputs the first signal, the movable roof may not always be at the fully closed position because the position of the movable roof is not always stable at the fully closed position by virtue of the construction of the movable roof relative to the vehicle body. Therefore, the locking mechanism may fail to switch to the locked condition from the unlocked condition. That is, the locking mechanism may not be in the locked condition even though the second signal is outputted to the control unit from the position sensor.
A need thus exists for an improved vehicle convertible top control apparatus that is able to address at least the drawbacks noted above.
According to one aspect of the invention, a control apparatus adapted to open and close a convertible top of a vehicle includes first detecting device for outputting a first signal representing that a movable roof of the vehicle is closed, a second detecting device for outputting a second signal representing that a locking mechanism is in a locked condition, a third detecting device for outputting a third signal representing that a driving mechanism is turned to an excessive load condition, and a control device for controlling the driving mechanism according to the first signal, the second signal and the third signal. The control device has a processing mechanism for executing an error step when the third signal is inputted to the control device and the second signal is not inputted to the control device while the first signal is inputted to the control device.
Another aspect of the invention involves a control apparatus for opening and closing a convertible top of a vehicle which includes a locking mechanism arranged between a movable roof and a vehicle body for holding the movable roof in a closed position and a motor operatively connected to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition upon supply of electric current. The control apparatus includes a closed condition detection switch that detects the closed position of the movable roof and outputs a signal upon detection of the closed position of the movable roof, a locked condition detection switch that detects the locked condition of the locking mechanism and outputs a signal upon detection of the locked condition of the locking mechanism, an excessive electric current detection circuit that detects excessive electric current supplied to the motor and outputs a signal upon detection of excessive electric current supplied to the motor, and a controller that receives the signals outputted from the closed condition detection switch, the locked condition detection switch and the excessive electric current detection circuit to stop operation of the motor when the controller, upon receiving the signal from the excessive electric current detection circuit after receiving the signal from the closed condition detection switch, does not receive the signal from the locked condition detection switch.
Another aspect of the invention involves a method for detecting an error associated with operation of a convertible top of a vehicle that includes a locking mechanism arranged between a movable roof and a vehicle body for holding the movable roof in a closed position and a driving mechanism operatively connected to the locking mechanism to drive the locking mechanism between a locked condition and an unlocked condition. The method includes detecting that the movable roof has reached a fully closed position, detecting an excessive load condition of the driving mechanism while the driving mechanism is driving the locking mechanism towards the locked condition, and determining the occurrence of an error upon detecting the excessive load condition of the driving mechanism after detecting that the movable roof has reached the fully closed position and in the absence of a detection that the locking mechanism has reached the locked condition.